The 12 Levers

How to Change Your Life with Things You Actually Control

Contributors

By Spencer Greenberg, PhD

By Jeremy Stevenson, PhD

Formats and Prices

On Sale
Jul 28, 2026
Page Count
272 pages
Publisher
Balance
ISBN-13
9780306837463

Price

$30.00

Price

$40.00 CAD

Format:

  1. Hardcover $30.00 $40.00 CAD
  2. Audiobook Download (Unabridged) $24.99

A clinical psychologist and an applied math psychology entrepreneur distill the collective wisdom of self-help into 12 core principles for self-improvement that are as simple to activate as switching a lever

The number of self-help books and psychological therapies out there is overwhelming. But, at their core, are all these books and therapies really teaching different things? That is, are there really that many self-help strategies out there? After spending years analyzing more than a hundred self-help books (from Tony Robbins to Tim Ferriss) and more than a dozen therapies (from CBT to EFT), Spencer Greenberg and Jeremy Stevenson propose that the answer is no.
Ultimately, it all boils down to just twelve effective strategies that underlie basically all of self-improvement. The 12 Levers offers to readers something they won’t find elsewhere: a single source to learn these twelve core strategies underpinning self-improvement and how to apply them, step-by-step. These 12 levers are situated in four successive categories:
  1. Clarify
  2. Act
  3. Overcome
  4. Cultivate
Thoughtfully assembled from their extensive analysis of the field and interwoven with fascinating stories about the originators and popularizers of these techniques, The 12 Levers will not only be simple and intuitive to implement, but compelling and thought provoking to read.
 


Spencer Greenberg, PhD

About the Author

Spencer Greenberg is an entrepreneur and mathematician with a specialization in psychology. He’s the founder and CEO of Spark Wave, a psychology research organization that designs and conducts novel experiments and studies in psychology, and builds psychology related products designed to help solve problems in the world (e.g. scalable care for mental health challenges, and technology for accelerating and improving social science research). Spencer is also the host of the Clearer Thinking podcast, which is in the top 1% of podcasts globally. Through it, Spencer has interviewed many self-help figures and prominent non-fiction authors such as Scott Barry Kaufman, Loch Kelly, Kristin Neff, AJ Jacobs, Oliver Burkeman and Nobel prize winner Daniel Kahneman. Previously, Spencer co-founded AskAMathematician.com, a mathematics question and answer site which had about 50,000 monthly page views. He also founded ClearerThinking.org, which offers over 75 self-improvement tools and training programs used by hundreds of thousands of people, which are designed to help you improve decision-making, increase positive behaviors, and reduce cognitive biases.

Spencer has a PhD in applied math from NYU, with a specialty in machine learning. Spencer’s work has been featured by numerous major media outlets, such as Forbes, The New York Times, the Wall Street Journal, the Independent, Lifehacker, Gizmodo, Fast Company, and the Financial Times. Spencer also has extensive public speaking experience having done multiple talks including two TEDx talks here and here.

Jeremy Stevenson has a PhD from Flinders University and has published in academic journals (e.g., here, here, here, here), as well as outside of academia here. In addition to print publications, he has also appeared on various media platforms like radio and newspaper discussing his research. As well as a researcher, Jeremy is a clinical psychologist and has accrued thousands of hours of experience across hundreds of clients. He has studied self-help techniques both inside and out. He’s received dozens of therapy hours himself and attributes some fundamental transformations to this experience with excellent therapists.
 
When he completed his PhD he took a year off to study mindfulness meditation intensively – sitting month long retreats in Australia and Malaysia before doing a three-month retreat in Nepal. He’s tried every single one of the major self-help approaches in our list, including an experience of imagery rescripting that permanently increased his self-compassion, as well as a self-transcendent experience on a meditation retreat that has dramatically reduced his suffering years later. Jeremy also has extensive public speaking experience – he once did a job in his early 20s selling volunteer travel packages at North American universities that involved racing around doing dramatic announcements to packed auditoriums as well as full days of information sessions. During his PhD he won Flinders University’s People’s Choice Award for the 3-Minute Thesis in 2015, a competition in which you present your thesis to a lay audience. Jeremy works with Spencer at Spark Wave. You can listen to Jeremy on Spencer’s podcast discussing meditation here.
 

Learn more about this author